Air operated projectile firing apparatus



July 21, 1970 J. E, VAN I ANGENHVEN 3,521,523

AIR OPERTED PROJECTILE FIRING APPARATUS Original Filed July 7, 1965 2 Sheets-Sheetl United States Patent O 3 521,523 AIR OPERATED PROJCTILE FIRING APPARATUS Jules Edmond Van Langenhoven, Benton County, Ark.,

assiguor, by mesne assignments, to Victor Comptometer Corporation, Chicago, Ill., a corporation of Illmols Application July 7, 1965, Ser. No. 473,556, which is a continuation-in-part of application Ser. No. 189.621, Apr. 23, 1962. Divided and this application July 18, 1968, Ser. No. 760,106

Int. Cl. F4115 1/00 U.S. Cl. 89-7 7 Claims ABSTRACT OF THE DISCLOSURE A device for firing a projectile having an associated propellant ignitable by surface contact with high temperature air in which an air cylinder is connected to a firing chamber at the rear of an axially movable barrel by an air passage extending through a breech member pivotally movable relative to the barrel and the air cylinder between a loading position and a firing position in which an obturated tiring chamber is formed between the barrel and the breech. The device may be provided with an automatic cooking system comprising coaxial air and gas expansion pistons mounted on a common piston rod.

SUMMARY AND BACKGROUND OF INVENTION This application is a division of copending application Ser. No. 473,556 filed July 7, 1965, which is a continuation-in-part of application Ser. No. 189,621 tiled Apr. 23, 1962, now abandoned. The invention relates to devices for firing a projectile having an associated propellant ignitable by surface contact Vwith high temperature air, and more particularly lto a new and improved powder actuted tool utilizing hot air ignition of a propellant to drive a stud or the like. The inventive concepts are illustratively embodied in a device in which an air compression cylinder is connected to a firing chamber by an air passage extending through a breech pivotally movable between a firing position and a loading position. In the preferred embodiment, the longitudinal axes of the barrel and the air cylinder are o'set. The breech is pivotally mounted on and pivots about the longitudinal axis of the air cylinder with the air passage extending radially from the air cylinder to the breech and axially from the breech to the tiring chamber. A further feature of the device is an automatic cooking system comprising a gas expansion piston-cylinder coaxial with the air cylinder and a common piston rod for the gas expansion piston and the air cylinder piston. It is to be recognized that the inventive concepts are applicable to firearms in general and, in particular, to air ignition system firearms of the type disclosed in the aforementioned oopending application.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view, in section, of a stud driving tool apparatus embodying the inventive principles;

FIG. 2 is a sectional view of the apparatus shown in FIG. 1 taken along the line 2 2;

FIG. 3 is an end view of the apparatus shown inA ice section, of an alternative form of stud for use with the apparatus of FIG. l.

DETAILED DESCRIPTION OF INVENTION Referring now to FIGS. 1-7, certain of the inventive principles are shown to be embodied in an illustrative powder actuated stud driving tool comprising a handle portion 600 formed from complementary handle halves 601, 602 (FIG. 3) and connected to a barrel portion 604 (FIG. l) in which air compression cylinder means 606 are connected through valve means in a breech block means assembly 607 to bore 608 of a barrel means assembly 609.

The air compression cylinder means 60'6 comprises a compression chamber 610 in which an air compression piston means 611 is reciprocably mounted on a piston rod 612 extending forwardly through the front wall 613 of the cylinder means and being connected at its forwardmost end to a gas expansion return piston means assembly 614 for automatic cooking of the tool. Compression spring means 616 is mounted about the piston rod and compressibly retained between a slidable sleeve element 618, abutting the return piston assembly, and the front wall 613 of the compression cylinder. A spring cushion arrangement l622 is mounted on the front of the return piston means to cushion the bottoming of the return piston assembly '614 at the front end 623 of the return cylinder means 624. As shown in FIG. 2, cylinder means 624 is provided with a high pressure inlet passage 626 connected to the barrel bore 608 through a passage 628 controlled by an adjustable valve 630. Thus, high temperature, high pressure gases, generated when the tool is fired, may be conducted into the return cylinder means 624 to cock the gun as will be hereinafter described in detail. After such a high pressure cooking operation, the gases in the cylinder 624 cool to reduce the pressure and the passage 628 to the barrel remains open so that during subsequent air compression in chamber `610 the return piston assembly 614 is freely movable.

A manual cooking mechanism is also provided and includes a cooking lever assembly 636 releasa'bly mounted at the front of the handle assembly by suitable catch means 637. The lever assembly comprises a main body portion 638 connected at 639 to an actuating link 640 pivoted at 641. An operating handle extension 642 is slidably mounted on the `body portion and may tbe downwardly displaced to increase the mechanical advantage for the manual cooking operation. Link 640 is pivotally connected at 643 (FIG. 4) to a connecting link 644 pivotally connected at 645 to a yoke 646 which straddles the return cylinder 624 and is slidable therealong. Pin means connected to the sleeve 618 form pivot 645 and are slidably mounted in slots 647, 648 extending along the return cylinder 624 and sleeve 618.

The piston assemblies are held in the cocked position by means of a pivotally mounted sear 649 which is engageable with an abutment 650 in a slot 651 in the sleeve 618 as shown in FIG. 5. A trigger mechanism is provided to release the sear and comprises a trigger 652 pivotally mounted at 653. An intermediate lever 654 is pivoted at 656 and has a cam abutment 658 adapted to engage a cam actuator portion 660 of the trigger. A spring Ibiased cam slide 661 is mounted on the intermediate lever and engages a cam portion 662 of the sear. A sear spring 664 biases the sear toward the latched position against a stop 665. Thus, when the trigger 662 is rotated about 653 against a return spring 666, cam portion 660 rotates lever 654 upwardly about 656 and slide 661 rotates sear 649 downwardly about pivot 667 against spring 664.

A locking mechanism s provided to prevent actuation of the trigger unless the tool has been preconditioned for operation by pressing the barrel assembly against the Work surface as will be hereinafter described in detail. A slidable latch bar 668 is engaged with a flat 669 on the intermediate lever 654 in the locked position shown in FIG. and is movable rearwardly to an unlocked position in alignment with the notched portion 670 of the intermediate lever. As shown in detail in FIG. 4, the bar 668 is connected to a sleeve `671 surrounding the bottom of the return cylinder 624 and fastened by a flange 670 to a flange 672 at 673. One end of a slidable sleeve 674, mounted about the barrel 609, is connected to the ange 672 at 675.

The barrel assembly comprises an elongated tubular member 676 which is reciprocably mounted for movement between a loading position (FIG. 1) and a firing position (-FIG. 6). The barrel is slidably journaled in a bore 677 in a housing 678 at the rear of the tool and in a sleeve 679 at the front of the tool. A spring 680, mounted between an abutment in a counterbore in the housing and an abutment formed by the rear end of sleeve 674 and a flange 681 on the barrel 675, biases the barrel forwardly to the loading position. Sleeve 679 is slidably journaled in a collar 682 at the front of the tool and supports a work engaging support shoe means 683. A spring 684 mounted between a stop 685, fixed to the return cylinder 624 biases the sleeve 679 and shoe assembly 683` outwardly. As shown in FIG. 3, shoe 683 has a curvilinear portion 686 and a rectangular portion 687 which are adjustably mounted on support plate means 688 by release screw means 689 so that the shoe may be rotated relative to the barrel to accommodate use of the tool in restricted areas such as building corners or the like. A support collar 690 is mounted on the front of the barrel and may include a recess 691 for magnetic reception and retention of washer means or the like to be associated with the driver stud. The other end of the barrel, FIG. 6, is provided with an enlarged obturation chamber 692 having a tapered approach surface 693 adapted to receive a correspondingly tapered portion of an obturator 694 mounted on the breech means assembly 607 as hereinafter described in detail.

Thus, in operation of the tool, the collar 690 is engageable with the work surface and movable rearwardly under pressure applied by the operator against the bias of the compression spring 680. The cup-shaped shoe 683 is also adapted to be seated on a surface surrounding the area of impact of the stud with the workpiece and is movablevrearwardly under pressure against the bias of the compression spring 684. `In this manner, the barrel is moved rearwardly to the tiring position and the latch bar 668 is moved rearwardly from the latched position to release the trigger mechanism due to the engagement of sleeve 674 with barrel abutment 681. In the firing position, FIG. 6, the compression chamber is connectable to the firing chamber by means of a port 700, valve means 702, valve chamber 704, and a passage 706, as shown in FIG. 1. The valve means comprises a ball valve adapted to be seated on a seat 709 in the movable breech means 607. Compression spring means 710 and an adjustable plug 711 for varying the tension on the spring may also be provided. Obturator 694 is formed as a plug which also may be threadably mounted or otherwise xedly secured in i the breech means 607. The outer surface of the obturator 694 is tapered to provide a mating fit with the wall of the enlarged tapered obturator chamber 692 at the end of the y barrel means as shown in FIG. 6. Thus, when the barrel is moved rearwardly, the obturator is positioned in the obturator chamber and the tool is ready to be red.

The breech means is pivotally movable from a position fr in alignment With the barrel means to a position spaced outwardly therefrom (not shown) to enable a stud to be positioned in the rear of barrel as indicated in FIG. 6.

purpose. Thus, the breech means is pivotally movable about the central longitudinal axis of the compression cylinder and the piston rod. The breech means is axially located between spaced abutments' and extends upwardly between the barrel means and a loading sleeve 714 having a loading port 716 opening at the rear of the tool. A manually operable catch 718 cooperates with spring biased detent means 720 to maintain the movable breech means in the closed firing position.

Referring again to FIG. 6, the projectile to be driven from the tool may take any of the conventional forms now available for use in tools of this general type. In the illustrative embodiment, the round of ammunition 730 comprises a projectile portion in the form of a stud having an elongated shank portion 732, terminating in a pointed end 733, and a headed portion 734. A propellant portion ofthe round of ammunition comprises, in the illustrative embodiment, plug means 736 attached to the projectile head portion and providing support means 738, obturation means 740, and propellant attaching means 742. The plug beans may be made of any suitable material such as plastic materials, lwhich will be capable of being compressed and driven through the barrel after ignition of the propellant. In the illustrative embodiment, the propellant 744 is mounted in a cavity at the rear of the plug with a surface exposed for surface contact with high temperature air delivered through passage 706. It will be understood that the propellant may be otherwise attached or associated with the projectile. Referring now to FIG. 7, an alternative projectile form is shown to comprise a threaded head portion 748 with the plug means 736 being generally cylindrical and molded or extruded onto the threaded head portion as shown. The barrel may be modied as necessary or desirable by, for example, providing an obturation shoulder for engagement with the surface 750. It will be understood that any other stud form may be utilized and, as is conventional, a guide ring 746 may be mounted on the front of the studs.

In the firing position, it will be observed that the propellant cap 744 is exposed in the tiring chamber for contact with high temperature air to be delivered from the air compression means during firing of the tool while the front edge of the plug 736 also serves to hold the stud in the barrel until the time that the propellant is ignited and the stud is driven down the barrel. `It may be observed that the ball valve is mounted to provide a positive reaction surface in the valve chamber so that the gases generated by ignition of the propellant are confined to the firing chamber and communication with the compression chamber is completely closed.

While the propellant is shown to be attached to the stud, it could be separately loaded. Furthermore, while in the illustrative embodiment, a free ight powder actuated tool is disclosed, certain principles of this invention are applicable to a piston driven type tool as will be readily understood by those skilled in the powder actuated tool art.

In the broadest aspects of the present invention it is contemplated that other types of propellant may be used and that other propellant ignition means may also be provided. However, particularly advantageous results are obtained by the use of therefor an air ignition system as disclosed.

The invention claimed is:

1. A device for firing a projectile having an associated propellant ignitable by surface contact with high temperature air comprising:

receiver means for supporting the operational mechanism of said device;

a source of high temperature air for ignition of the propellant by surface contact therewith comprising air compression cylinder means mounted on said receiver means, piston means movably mounted in said cylinder means for movement between a retracted position and an extended position during an air compression stroke, piston driving spring means for driving said piston during a compression stroke;

sear means for latching said piston means in the retracted position; A

trigger means for releasing said sear means to initiate a compression stroke;

barrel means mounted on said receiver means and extending parallelly to said compression chamber means for guiding the projectile from said device after ignition of the propellant;

ammunition loading means provided at the rear of said barrel means;

movable breech means mounted between said barrel means and said loading means for movement bebetween a iiring position in line with said barrel means and a loading position located outwardly of said barrel means;

said breech means having an eccentric bore and said compression cylinder means extending through said bore and pivotally supporting said breech means for pivotal movement between a ring position in line with said barrel means and a loading position located outwardly of said barrel means;

obturation means provided on said breech means and said barrel means for cooperative engagement in the ring position;

tiring chamber means provided Within said obturation means by an enlarged chamber adapted to surround the propellant; and

high temperature air delivery means connecting said air compression cylinder means to said tiring chamber means to deliver high temperature air from said compression cylinder means to said firing chamber means for ignition of the propellant by surface contact therewith.

2. The invention as defined in claim 1 and comprising a radially extending passage extending from said air compression cylinder means into said breech means and an axially extending passage connected to said radially extending passage in said breech means and extending from said breech means to said firing chamber means to deliver high temperature air from said compression cylinder means to said tiring chamber means for ignition of the propellant by surface contact therewith.

3. A device for firing a projectile having an associated propellant ignitable by surface contact lwith high temperature air comprising:

receiver means for supporting the operational mechanism of said device;

a source of high temperature air for ignition of the propellant by surface contact therewith comprising air compression cylinder means mounted on said receiver means, piston means movably mounted in said cylinder means for movement between a retracted position and an extended position during an air compression stroke, piston driving spring means for driving said piston during a compression stroke;

sear means for latching said piston means in the retracted position;

trigger means for releasing said sear means to initiate a compression stroke;

barrel means mounted on said receiver means and extending parallel to said air compression cylinder means for guiding the projectile from said device after ignition of the propellant;

ammunition loading means provided at the rear of said barrel means;

movable breech means mounted between said barrel means and said loading means for movement between a tiring position in line with said barrel means and a loading position located outwardly of said barrel means;

obturation means provided on said breech means and said barrel means for cooperative engagement in the firing position;

firing chamber means provided within said obturation means by an enlarged chamber adapted to surround the propellant;

a radially extending passage extending from said air compression cylinder means into said breech means and an axially extending passage connected to said radially extending passage in said breech means and extending from said breech means to said tiring chamber means to deliver high temperature air from said compression cylinder means to said firing chamber means for ignition of the propellant by surface contact therewith; and

high temperature air delivery means connecting said air compression cylinder means to said firing chamber means to deliver high temperature air from said compression cylinder means to said tiring chamber means for ignition of the propellant by surface contact therewith.

4. A device for tiring a projectile having an associated propellant ignitable by surface contact with high temper-ature air comprising:

receiver means for supporting the operating mechanism of the device;

barrel means mounted on said receiver means for guiding a projectile from the device;

cylinder means mounted parallel to said barrel means in said receiver means;

cylinder head means dividing said cylinder means into an air compression chamber and a gas expansion chamber;

air compression piston means mounted in said air compression chamber;

gas expansion piston means mounted in 'said gas expansion chamber;

common piston rod means connecting said air compression piston means and said gas expansion piston means for simultaneous reciprocation thereof;

spring means for driving said air compression piston means from a retracted position to an extended position during a compression stroke and biasing said air compression piston means and said gas expansion piston means toward an extended position;

sear means for holding said piston means in the retracted position;

trigger means for releasing said sear means to initiate a compression stroke;

manually operable cooking means connected to said piston means for moving said piston means to the retracted position comprising a manually operable cooking lever;

power operable cooking means for automatically moving said piston means to the retracted position comprising passage means connecting said barrel means and said gas expansion chamber to deliver high ternperature propellant generated gases from s-aid barrel means to said gas expansion means during firing of the device and causing movement of said gas expansion piston means to the retracted position;

firing chamber means formed about the propellant in the tiring position; and

air passage means extending from said air compression chamber means to said tiring chambermeans to deliver high temperature air to said tiring chamber means during the compression stroke to ignite the propellant.

5. A device for ring a projectile having an associated propellant ignitable by surface contact with high temperature air comprising:

receiver means for supporting the operational mechanism of the device;

barrel means for guiding the projectile from the device after ignition of the propellant;

ammunition holding means for holding a projectile and associated propellant in a firing position aligned with said barrel means;

barrel support means mounted on said receiver means and slidably supporting said barrel means for axial movement relative to said receiver means between a firing position and a loading position;

pivotally movable breech means mounted in said receiver means for pivotal movement between a ring position and a loading position;

tiring chamber obturation means provided by an enlarged chamber on the end of said barrel means about said ammunition holding means;

ring chamber obturation means provided by a projecting plug on said breech means matingly corresponding with said enlarged chamber, said projecting plug adapted to be matingly received within said enlarged chamber in the ring position of said barrel means and said breech means;

ring chamber means formed in said projecting plug and being ladapted to receive and surround the propellant portion of the ammunition in the ring position;

a source of high temperature air having a temperature at which the propellant is ignitable by surface contact therewith comprising air compression means and piston means movable therein to compress -air during an air compression stroke, piston driving spring means associated with said piston means to drive said piston means from a retracted position to an extended position during an air compression stroke;

sear means to latch said piston means in the retracted position;

trigger means to selectively release said sear means to initiate an air compression stroke;

cocking means to move said piston means to the retracted position against the bias of said piston driving spring means; and

air delivery means for delivering high temperature air from said air compression means to said tiring chamber means comprising passage means extending through said breech means and terminating in said firing chamber means.

6. A device for ring a projectile having an associated propellant ignitable by surface contact with high temperature air comprising:

barrel means for guiding the projectile from the device after ignition of said propellant; ammunition holding means for receiving the projectile and the propellant in a loading position and for carrying the projectile and the propellant from the loading position to the firing position and for holding the projectile and the propellant in a firing position in alignment with said barrel means prior to ignition of said propellant;

air compression means providing a source of high tempe-rature air having a temperature at which the propellant is ignitable by surface Contact therebetween and being connected to said barrel means through said ammunition holding means in the tiring position;

means for separating said air compression means from said barrel means by pivotal movement transverse to the longitudinal axis of said barrel means;

tiring chamber means formed about the propellant in the tiring position;

air delivery means connecting said air compression means to said firing chamber means to deliver high temperature air from said air compression means to said ring chamber means at a temperature at which the propellant is ignitable by surface contact therebetween; and

obturation means effective in the firing position between the barrel means and the ammunition holding means and between the air delivery means and the ammunition holding means.

7. The invention as defined in claim 6 and having additional means for separating said air compression means from said barrel means by axial movement of said barrel means relative to said air compression means.

References Cited UNITED STATES PATENTS 1,962,946 6/1934 Andrews 124-15 3,008,258 11/1961 Johnson 42-14 3,064,381 11/1962 Vilbajo.

FOREIGN PATENTS 5,317 1826 Great Britain. 711,542 7/ 1954 Great Britain.

SAMUEL W. ENGLE, Primary Examiner U.S. Cl. X.R. 

